plural jacks
Definition of jack
(Entry 1 of 2)
1a
jacks plural in form but singular in construction
: a game played with a set of small objects that are tossed, caught, and moved in various figures
b
: a small 6-pointed metal object used in the game of jacks
2a
: a playing card carrying the figure of a soldier or servant and ranking usually below the queen
3
: any of various usually mechanical devices: such as
a
: a usually portable mechanism or device for exerting pressure or lifting a heavy body a short distance
b
: a device for turning a spit
4
: a female fitting in an electric circuit used with a plug to make a connection with another circuit
6
: something that supports or holds in position: such as
a
: an iron bar at a topgallant masthead to support a royal mast and spread the royal shrouds
b
: a wooden brace fastened behind a scenic unit in a stage set to prop it up
7a
: any of several fishes
especially
: any of various carangids
b
: a male donkey
c
: jackrabbit
d
: any of several birds (such as a jackdaw)
8a
: a small white target ball in lawn bowling
b
: a small national flag flown by a ship
11
: jackknife sense 2
12
: monterey jack
13
US slang
: anything at all
—used in negative constructions In short, Dinger or Homer or whoever it was who wrote the Odyssey didn't know jack about travel.— Steve Rushin
jack
verb
jacked; jacking; jacks
Definition of jack (Entry 2 of 2)
1
: to move or lift (something) by or as if by a jack (see jack entry 1 sense 3a) : jack up
It meant that we had to jack the aircraft and check out the undercarriage system …— John Revell Over 500 tons of pressure was used to jack the legs of the [Gateway] Arch apart for the last four-foot piece to be inserted at the top. — nps.gov
b
: to increase in intensity, scope, etc. : jack up
In the same light, any student has heard of someone taking self-prescribed Adderall to jack their focus for the next big exam.— Zeno Yeates
3a
informal
: steal
"She jacked my pencil" one boy screamed. "But only because he jacked my pen" the girl yelled back.— Jason Kane
especially
: to steal (a car)
A man is accused of stealing from a Bradenton hardware store and then jacking a nearby car … — Giuseppe Sabella
b
informal
: rob
jack a store Droopy was always promising to rob old ladies, but so far had jacked only a pizza delivery man …— Gini Sikes
4
informal
: to cause great excitement, enthusiasm, or energy in : jack up
Even Phil Mickelson, the Masters champion of a year ago and a three-time winner in 2005, can't jack the audience like Woods.— Gerry Dulac
5
: to hunt or fish for (an animal) at night with a jacklight or similar bright light
… if old-fashioned country stores were anything like ours is today, you could find just about any type of gossip you might want, from suspicions about who is jacking deer out of season to the darkest speculation about marital infidelities. — Cook's Illustrated
6
informal
: to copy or appropriate (something, such as an idea or style) : hijack sense 2a
Apparently I'd struck a nerve in that sensitive place called the male ego. In his mind I'd accused him of hip-hop's equivalent of treason—jacking someone's style.— Dream Hampton
7
informal
: to hit (a ball) forcefully
Five batters later Martinez jacked an upper-deck grand slam off Mark Langston …— Tom Verducci Big Mac turns it up another notch, jacking five homers in his last 11 at-bats to finish with an unreal 70. — ESPN … Mickelson took an aggressive line off the tee and jacked a lob wedge over the green.— Alan Shipnuck
8a
informal
: to grab, shove, or handle (someone or something) forcefully : jack up
Behind the building he was greeted by several bruisers looking for blood. "One guy jacked my horn out of my arms and threw it down," he [Ornette Coleman] says.— David Grogan
b
informal
: to cause injury to (someone or something) : jack up
The next week, he jacked his knee in a practice incident …, and it set him back a bit. — racerxonline.com
c
informal
: to beat up or hurt (someone) : jack up
Cejudo dropped Cruz with that knee and was jacking him with punches with no real response from Cruz.— Dan Bernstein
d
informal
: to treat or confront (someone) in a harassing, rough, or overly aggressive and typically unwarranted manner : jack up
"I honestly think the only reason I get jacked by the police is because I'm tall and black," said Maurice [St. Cyere], who is 5'9". — The Bay State Banner
: to hunt or fish at night with a jacklight or similar bright light
"… jacking involves the use of a high-powered light and a firearm at night. … Whether you are successful in getting a deer or not, it is an illegal act."— Blaine Henshaw
Buying Guide
Our Reviews team has selected the best gaming headsets.
Test Your Vocabulary
Name That Color
-
- Name that color:

Test your visual vocabulary with our 10-question challenge!
TAKE THE QUIZ
A daily challenge for crossword fanatics.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridged
Share jack
Time Traveler for jack
The first known use of jack was in 1548
See more words from the same year